John Duns Scotus (c. 1266 – November 8, 1308) was a theologian and philosopher. Some may argue that during his tenure at Oxford, the notion of what differentiates theology from philosophy and science began in earnest.
He was born in Duns, Scotland. Ordained a priest in Northampton, England, he studied and taught at Oxford and Paris and probably also at Cambridge. Finally, he came to Cologne in 1307.
He was one of the most important Franciscan theologians and was the founder of Scotism, a special form of Scholasticism. He was known as Doctor Subtilis because of his subtle merging of differing views.
However later philosophers were not so complimentary about his work and the modern word dunce comes from the name "Dunse" given to his followers.
He died in Cologne and is buried in the Church of the Minorites in Cologne. His sarcophagus bears the Latin inscription: "Scotia me genuit. Anglia me suscepit. Gallia me docuit. Colonia me tenet." ("Scotland brought me forth. England sustained me. France taught me. Cologne holds me.") He was beatified by Pope John Paul II in 1993.
Perhaps the most influential point of Duns Scotus' theology was his defense of the Immaculate Conception of Mary. At the time, there was a great deal of argument about the subject. The general opinion was that it was appropriate, but it could not be seen how to resolve the problem that only with Christ's death would the stain of original sin be removed. The great philosophers and theologians of the west were divided on the subject (indeed, it appears that even Thomas Aquinas sided with those who denied the doctrine, though some Thomists dispute this). The feast day had existed in the East since the seventh century and had been introduced in several dioceses in the West as well, even though the philosophical basis was lacking. Citing Anselm of Canterbury's principle, "potuit, decuit, ergo fecit" ([God] could do it, it was appropriate, therefore he did it), Duns Scotus devised the following argument: Mary was in need of redemption like all other human beings, but through the merits of Jesus' crucifixion, given in advance, she was conceived without the stain of original sin.
This argument appears in Pope Pius IX's declaration of the dogma of the Immaculate Conception. Pope John XXIII recommended the reading of Duns Scotus' theology to modern theology students.